I would probably ask Aruba Support. What I can imagine is that the NVRAM battery is empty, so the boot settings are lost when the server is powered off for some time.
Did you see messages around lost settings/NVRAM during the startup? BTW, for ClearPass 6.11+ you would need UEFI boot, for versions 6.10 and below it would be legacy BIOS boot. But an empty battery is annoying anyway. Not sure what the policy is for that, as replacing the (CR2032) battery is relatively simple but it may void your warranty, so best to work with support.
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Herman Robers
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If you have urgent issues, always contact your Aruba partner, distributor, or Aruba TAC Support. Check
https://www.arubanetworks.com/support-services/contact-support/ for how to contact Aruba TAC. Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or Aruba Networks.
In case your problem is solved, please invest the time to post a follow-up with the information on how you solved it. Others can benefit from that.
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